If a hurricane rotates in one direction and a cyclone rotates in
the other, what happens if they cross the equator?

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If a hurricane (northern hemisphere) rotates in one
direction and a cyclone (southern hemisphere) rotates in the other,
what happens if they cross the equator?

They never cross the equator, nor do they occur near it.
Hurricanes and cyclones are born in waters at least eight degrees
north or south of the equator. The rotation of the earth sends them
off on a track that arcs away from the equator.Jeffrey Mellefont, Bondi Beach

This rotational force is zero at the equator and increases as
you travel away from the equator, being greatest at the poles.
Hurricanes and cyclones can't actually form within 4 degrees of the
equator, because the Coriolis effect is just too small. Once a
tropical revolving storm is formed though, wind determines its
movement. There is very little cross-equatorial flow of wind, as
the main winds steer the storm away from the equator. So it is
almost impossible for a tropical storm to cross the equator.David Buley, Seaforth

Hurricanes and cyclones are low pressure systems. When they form
you'd expect the surrounding higher pressure air to flow in
radially. But minute forces, caused by the earth's rotation, make
the wind flowing towards the low pressure rotate - anticlockwise
northern hemisphere, clockwise southern. They're called Coriolis
forces. Now imagine a low pressure forming in the southern
hemisphere. The first tiny breezes trying to fill the low pressure
are made to rotate in a clockwise direction. The low pressure
deepens and what was a breeze is now a cyclone. If the cyclone now
moves north across the equator the Coriolis forces - now
anticlockwise - will try to reverse the rotation, but they're far
too small to have any effect. The cyclone will continue to rotate
in a clockwise direction.Jon Sarvis, Maianbar

The correct names for the topical storms in either hemispheres
is Tropical Revolving Storms (TRS). Other names are usually local
to an area eg. Hurricane, Spanish, hurakan, god of the storm, or
typhoon from the Chinese dialect, tai fung or big wind. The earth's
rotation, the geostrophic effect, determines the direction of
rotation of the TRS and in the northern hemisphere it is anti-clock
wise or left handed and in the southern hemisphere it is clock wise
or right handed. The storms originate generally between 7 and 15
degrees latitude, south or north. They travel initially in a
direction of between west to south-west in the southern hemisphere
and west and north-west in the northern hemisphere. They generally
recurve (change course about 90 degrees to their original course
line) at 25 degrees latitude, may be lower in southern hemisphere,
and take a direction of north-east in the northern hemisphere or
south-east in the southern hemisphere. The formation of a TRS
occurs over the ocean as a result of the differential heating
between the air and the sea, this causes spiralling thermal
currents which gather intensity resulting in a low pressure system.
They always travel away from the equator and therefore never cross
it. (see http://www.bom.gov.au/ for further
info).Mick Costelloe, South Coogee

A hurricane is the name used for a cyclone in the Caribbean.
Typhoon is the equivalent in the seas of Asia. It has nothing to do
with rotation or hemisphere.Niall Clugston, Parramatta

Cyclones can't ever cross the equator. They occur mainly between
10 and 20 degrees north or south of the equator and are the product
of tropical low pressure systems over warm water (plus a few other
factors too complex to mention here). The direction the winds flow
around a cyclone (and in fact any weather system) is determined by
the Coriolis effect. The Coriolis effect is created by the earth's
rotation. The result is wind in the southern hemisphere is
deflected to the left. So rather than flowing straight from high to
low pressure areas, as would be expected, the winds flow clockwise
around a low and anti-clockwise around a high. Within 10 degrees of
the equator, a region known to sailors as the doldrums, the
Coriolis effect is too weak to sustain this flow of wind. Hence,
cyclones are weakened as they approach the equator because they
lose one of forces that create and sustain them.Stu Nettle, Cronulla

Hurricanes, cyclones and typhoons never cross the equator. The
coriolis effect that initiates and drives the cyclones' rotation,
weakens to nothing at the equator. Cyclones tend to track away from
equator because of the Coriolis effect. However, any cyclone
tracking towards the equator would quickly lose angular momentum
and peter out. See http://www.bom.gov.au/bmrc/pubs/tcguide/ch1/figures-ch1/figure1.9.htm
Richard
Stanaway, Braddon (ACT)

When either one crosses the equator they decide to change their
names from one to the other: ie Hurricane to Cyclone and
visa-versa. I mean who is big enough to argue with either of them,
anyway!!!Neil Feller, Potts Point

They don't cross the equator. The hurricane belongs strictly to
the Caribbean: the word is West Indian, then Spanish. Another
circular storm of the northern hemisphere is the typhoon. Cyclones
belong in the Indian Ocean, too, in the northern hemisphere. Having
sailed through a typhoon, the last thing I was worried about was
the direction of rotation!Brian McNamara, Lyneham (ACT)

They won't! Imagine a moving conveyor belt (the equator) with
guide wheels in contact with it above and below
(hurricanes/cyclones). The guide wheels above the conveyor belt
rotate in an opposite direction to the wheels below. The earth's
rotation on its axis each day causes its atmosphere to divide into
"bands". These bands further contain eddies (the "guide wheels")
that circulate in opposite directions on either side of the equator
(the "conveyor belt"). This formation of distinct bands is a
powerful process so that the circulating eddies of air
(hurricanes/cyclones) are no more likely to cross from one
hemisphere to another and change their spin direction that a guide
wheel is likely to move to the other side of a moving conveyor belt
to spin in the opposite direction.Alex Abbey, Parkes

Did dinosaurs have a scent and, if so, what was it
like?

We are what we eat, so it's a safe bet that dinosaur herbivores
would smell like cattle or sheep, swamp dwellers like
hippopotamuses and carnivores like the big cats. Pop around to the
local zoo for a sample sniff.J. Barrie Brown, Gordon

This rotational force is zero at the equator and increases as
you travel away from the equator, being greatest at the poles.
Hurricanes and cyclones can't actually form within 4 degrees of the
equator, because the Coriolis effect is just too small. Once a
tropical revolving storm is formed though, wind determines its
movement. There is very little cross-equatorial flow of wind, as
the main winds steer the storm away from the equator. So it is
almost impossible for a tropical storm to cross the equator.David Buley, Seaforth

Hurricanes and cyclones are low pressure systems. When they form
you'd expect the surrounding higher pressure air to flow in
radially. But minute forces, caused by the earth's rotation, make
the wind flowing towards the low pressure rotate - anticlockwise
northern hemisphere, clockwise southern. They're called Coriolis
forces. Now imagine a low pressure forming in the southern
hemisphere. The first tiny breezes trying to fill the low pressure
are made to rotate in a clockwise direction. The low pressure
deepens and what was a breeze is now a cyclone. If the cyclone now
moves north across the equator the Coriolis forces - now
anticlockwise - will try to reverse the rotation, but they're far
too small to have any effect. The cyclone will continue to rotate
in a clockwise direction.Jon Sarvis, Maianbar

The correct names for the topical storms in either hemispheres
is Tropical Revolving Storms (TRS). Other names are usually local
to an area eg. Hurricane, Spanish, hurakan, god of the storm, or
typhoon from the Chinese dialect, tai fung or big wind. The earth's
rotation, the geostrophic effect, determines the direction of
rotation of the TRS and in the northern hemisphere it is anti-clock
wise or left handed and in the southern hemisphere it is clock wise
or right handed. The storms originate generally between 7 and 15
degrees latitude, south or north. They travel initially in a
direction of between west to south-west in the southern hemisphere
and west and north-west in the northern hemisphere. They generally
recurve (change course about 90 degrees to their original course
line) at 25 degrees latitude, may be lower in southern hemisphere,
and take a direction of north-east in the northern hemisphere or
south-east in the southern hemisphere. The formation of a TRS
occurs over the ocean as a result of the differential heating
between the air and the sea, this causes spiralling thermal
currents which gather intensity resulting in a low pressure system.
They always travel away from the equator and therefore never cross
it. (see http://www.bom.gov.au/ for further
info).Mick Costelloe, South Coogee

A hurricane is the name used for a cyclone in the Caribbean.
Typhoon is the equivalent in the seas of Asia. It has nothing to do
with rotation or hemisphere.Niall Clugston, Parramatta

Cyclones can't ever cross the equator. They occur mainly between
10 and 20 degrees north or south of the equator and are the product
of tropical low pressure systems over warm water (plus a few other
factors too complex to mention here). The direction the winds flow
around a cyclone (and in fact any weather system) is determined by
the Coriolis effect. The Coriolis effect is created by the earth's
rotation. The result is wind in the southern hemisphere is
deflected to the left. So rather than flowing straight from high to
low pressure areas, as would be expected, the winds flow clockwise
around a low and anti-clockwise around a high. Within 10 degrees of
the equator, a region known to sailors as the doldrums, the
Coriolis effect is too weak to sustain this flow of wind. Hence,
cyclones are weakened as they approach the equator because they
lose one of forces that create and sustain them.Stu Nettle, Cronulla

Hurricanes, cyclones and typhoons never cross the equator. The
coriolis effect that initiates and drives the cyclones' rotation,
weakens to nothing at the equator. Cyclones tend to track away from
equator because of the Coriolis effect. However, any cyclone
tracking towards the equator would quickly lose angular momentum
and peter out. See http://www.bom.gov.au/bmrc/pubs/tcguide/ch1/figures-ch1/figure1.9.htm
Richard
Stanaway, Braddon (ACT)

When either one crosses the equator they decide to change their
names from one to the other: ie Hurricane to Cyclone and
visa-versa. I mean who is big enough to argue with either of them,
anyway!!!Neil Feller, Potts Point

They don't cross the equator. The hurricane belongs strictly to
the Caribbean: the word is West Indian, then Spanish. Another
circular storm of the northern hemisphere is the typhoon. Cyclones
belong in the Indian Ocean, too, in the northern hemisphere. Having
sailed through a typhoon, the last thing I was worried about was
the direction of rotation!Brian McNamara, Lyneham (ACT)

They won't! Imagine a moving conveyor belt (the equator) with
guide wheels in contact with it above and below
(hurricanes/cyclones). The guide wheels above the conveyor belt
rotate in an opposite direction to the wheels below. The earth's
rotation on its axis each day causes its atmosphere to divide into
"bands". These bands further contain eddies (the "guide wheels")
that circulate in opposite directions on either side of the equator
(the "conveyor belt"). This formation of distinct bands is a
powerful process so that the circulating eddies of air
(hurricanes/cyclones) are no more likely to cross from one
hemisphere to another and change their spin direction that a guide
wheel is likely to move to the other side of a moving conveyor belt
to spin in the opposite direction.Alex Abbey, Parkes

When did the fortepiano become the pianoforte and
why?

It didn't. Bartolomeo Cristofori's invention of about 1700 was
called "gravecembalo col piano e forte" or "harpsichord with soft
and loud". Today we call it "piano" for short. There were two
divergent streams of piano development in the 18th century,
although the terms were used somewhat inconsistently. The Viennese
fortepiano - favoured by the great composers because of its
intimate and direct action, with hammers connected to the keys -
continued to be made past World War I. The modern piano grew out of
the English-style pianoforte, with its more cumbersome action of
separately suspended hammers being poked towards the strings -
louder and much less subtle.Carey Beebe, Peakhurst

The terms "fortepiano" and "pianoforte" have been used
interchangeably throughout history for the successor to the
harpsichord. Today what we call the fortepiano is generally
understood to mean those instruments which used the Viennese
action, which had a shallower "key fall" and which produced a
lighter and less sonorous sound than the English and other European
equivalents. The Viennese action (used by composers like Haydn,
Mozart and Beethoven) gradually fell out of favour during the 19th
century probably owing to the rise of the virtuoso pianists like
Liszt.Scott Hannigan, Redfern

In the 19th century, farmers having a hard time growing crops
were called "cockatoo farmers" because only cockatoos were visible
in their fields. This was later shortened to "cockie farmers", then
"cockies".Rob Woof, South Hurstville

Squatters referred contemptuously to free selectors as cockatoos
because "they look upon them ... as plunderers and encroachers on
their wild woods, settling down upon them as the cockatoos do on
the ripening corn." (William Howitt's Land, Labour and Gold,
1855.)Gary Whale, Yamba

Cockies is short for cockatoos. When cockatoos feed in the wild,
they scratch around on the ground in the dirt looking for seeds,
just as farmers scratch around in the dirt to make a living. This
term was invented by shearers more than 100 years ago and is mildly
condescending.Lachlan MacDonald, Toowoomba

Early small holding farmers struggled to make a living. They
were battlers who scratched a living from soil that had never been
tilled before, trying to raise crops and keep away large flocks of
cockatoos or cockies. They were jokingly called cockatoo farmers
meaning that they appeared to be raising more cockatoos than
anything else. This was shortened to "cocky-farmers", until the
second part was dropped, and now by transfer, we have cow-cockies
and various other sorts of cocky, all of them farmers.David Buley, Seaforth

The 19th century Bulletin first coined the association
between our farmers and the few species of native birds who thrived
on their cleared and grazed land - the cockatoos. The name of these
icons was affectionately abbreviated to cockies once it was
realised how readily they became the noisy pets of society at
large, and could even learn by rote to repeat amusing nonsense
like, "Pretty drought relief !" "Cocky wants a hand-out!" and
"Who's a silly chook then?"L.Leroux, O'Connor (ACT)

The term is derived from one of the many tactics employed by the
large land-holding squatters to avoid the impositions of the Free
Selection Acts of the early 1860s. It was called "Peacocking" and
involved buying up land with river frontage or which enclosed a
waterhole so the intermediate land was valueless to the new
settlers.John McNamara, Yamba

They are two different classes. The old rule was: Over 5000
acres a grazier; under 5000 acres a cocky. A refinement of the rule
was: The larger the brim, the smaller the property.Brian McNamara, Canberra

The term was originally used derisively by other colonists to
describe the original squatters who settled on prime grazing land
(without the initial official blessing of the government) much as a
large, noisy flock of cockatoos might descend to drink at a water
hole. The name for these noisy squatter "cockatoos" was gradually
contracted to "cockies". Ironically, as land was gradually opened
up to smaller landholders, the squatters used the term to criticise
these new threats to their pastoral pre-eminence. With typical
Australian ironic humour the small landholders came to accept this
jibe as a badge of honour so that the term "cocky" is now
synonymous with a hard-working family farmer, not unlike that other
iconic Australian, "The Battler".Alex Abbey, Parkes

The word cocky refers more specifically to farmers who make a
living growing crops. Before the advent of chemical farming,
cockies would spend many hours on their tractors cultivating or
scratching up the ground in order to prepare a seedbed for their
crops. A similarity was drawn to the cockatoo that spends much of
its time doing likewise in order to get a feed. The term has
ultimately spread to any farming person, and then on to land owners
generally.Stuart Hulme, Holbrook

The term "cockie" refers more to farmers who grow crops than to
graziers. Supposedly they scratch in the dirt like cockies to plant
their seed.Victoria Harrington, Thirroul

The somewhat derogatory term "cocky" was originally given to
farmers who grew crops, because of the parrots which follow the
harvesters, feeding on spilt grain. Graziers, or pastoralists, who
gained most of their living from grazing animals, were never called
"cockies".

Each were once politically separated under their own state and
national unions. These groups have now largely amalgamated and the
term "farmer", and hence "cocky", increasingly applies to all who
derive their income from agriculture.Wendy Wilson, Dubbo

Why do we say we are "sick as a dog" when we are
unwell?

The phrase "sick as a dog" meaning "really ill" dates from the
17th century. While we know dogs will eat anything, on those
occasions when their diet disagrees, the result can be unpleasant.
Australians consider being "sick" as having a bad cold or such, but
the British take it literally - being "sick" would be taken as "to
vomit". With dogs, they eat some grass ... and I'll leave the rest
to your imagination.Robert Eason, Newtown

Among the many negative remarks concerning dogs is this pithy
phrase from Proverbs: "As a dog returneth to its own vomit, so a
fool returneth to its folly"(1). Paul Keating was once roundly
criticised for using the first part to lambast an opponent.
Keating's outraged critics would have been as sick as a dog when
they discovered what they thought to be the product of a disgusting
mind came from The Good Book.Paul Roberts, Lake Cathie

Why did the name Jack come to mean nothing, as in "I did
Jack"?

Obviously, your correspondent doesn't know Jack. Jack is an
ancestor of Average Joe and his portrait can still be seen on
playing cards. He has given his name to devices that save the
labour of the working man. He has also given his name to the male
of various species, such as the jackass. Since the male animal is
often larger, his name is used to denote a large version of
something, such as the jackknife and jackpot. So Jack doesn't mean
nothing, it means a whole lot of nothing - or whatever your
correspondent was doing ...Niall Clugston, Parramatta

ANY ANSWERS?

· A man is knighted. What is the equivalent term when a
woman is made a dame?

· What is the origin of "tomboy?"

· If my heart races playing poker, does that count as part
of my cardiovascular exercise routine?

· Why does all garbage smell the same?

· How did euphemisms come about?

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